There has been a growing interest in the development of scintillator materials with (1) good stopping power for gamma rays, (2) high light output, (3) proportional response, and (4) large, transparent, low cost crystals. Current known scintillators, such as Bi4Ge3O12 (BGO), NaI:Ti, BaF2, Lu2SiO5:Ce (LSO), LaBr3:Ce fall short in one or more of these properties.